1. Field of the Invention
This invention generally relates to equipment for lithography processes, and more particularly to a tool and a process for removing particles from a reticle.
2. Description of Related Art
In a lithography process, one of the key factors affecting the pattern quality is the quality of the reticle. To improve the quality of the reticle, some may improve the manufacturing process of the reticle, protect the pattern on the reticle from damage, or prevent particles from adhering to the reticle.
To protect the pattern on the reticle from damage, a pellicle is usually disposed on the reticle. Moreover, to prevent the exposure process from being affected by particles, when the reticle is entered into the loader of the mask aligner, a pellicle particle detector (PPD) is used to detect particles. If particles are detected on the reticle, the operator will unload the reticle and use a gas spray gun to remove the particles from the reticle. Then, the operator will reload the reticle into the PPD to check whether there are particles remaining on the reticle or not. This procedure would take a long time and increase the burden of the operator. Furthermore, the reticle may be damaged due to the operators negligence.